1. Field of the Invention
This invention generally relates to a system for cleaning H.V.A.C. ducts, and more specifically to a portable, combustion-driven blower system for cleaning H.V.A.C. ducts.
2. Related Art
It is common knowledge that when an H.V.A.C. system has been in use for a number of years, the ducts accumulate dirt, dust and various other contaminants which can be harmful to the individuals breathing air from such ducts. Many ducts are never cleaned and others are cleaned infrequently by antiquated methods.
The xe2x80x9csickxe2x80x9d building syndrome is receiving considerable attention and the government is considering drafting clean air standards for buildings. Indoor air has found to be up to 70 times more polluted air than outdoor air according to the EPA. Also, 50% of all illnesses are caused or aggravated by polluted indoor air as reported by the American College of Allergists. A dirty heating, ventilation and air conditioning system is a prime cause of indoor air problems and illnesses.
Various apparatus do exist for scraping and vacuuming ducts, but no particular system has received widespread acceptance. Most ducts are never cleaned, particularly in households, and even where an attempt is made at cleaning, the job is slow, laborious and expensive.
The system of the present invention proposes a portable, yet powerful system which can be wheeled into position, interconnected with a commercial or residential H.V.A.C. duct system, and utilized to clean the ductwork more efficiently and at a lower cost than heretofore possible.
Previous efforts in this area include International Publication No. WO 85/02565 to Hinkanen, which discloses a device for cleaning ventilating duct systems comprising a brush for brushing debris off the interior of a duct, a suction pipe having an opening at the brush, a suction fan for creating a suction in the suction pipe, and a filter at the suction side of the fan to prevent the fan from getting dirty. A motor rotates both the brush and the suction fan. The suction fan is a centrifugal fan.
U.K. Patent Application No. 8,123,820 to Kullik, discloses a vacuum cleaner having a suction blower driven by an electric motor. The flow of air through the system is monitored by a transducer connected to a regulating circuit to adjust the motor speed to maintain the air flow strength through the vacuum in a self-regulating manner. The transducer comprises an air turbine, driven by the air flow in the apparatus, interconnected with a generator.
Powell, U.S. Patent No. 5,438,729, discloses an apparatus for cleaning air ducts comprising a motor driven fan for developing a vacuum for the suction of contaminants in the air from the interior of the ducts by forcing the contaminated air stream under positive pressure through filtration, which air is then discharged locally within the building.
Szabo, U.S. Pat. No. 3,381,328, discloses a vacuum cleaner inlet coupling and air regulator for a vacuum cleaner.
Weber, et al., U.S. Pat. No. 4,473,921, discloses a cleaning device for ducts comprising an instrument carrier having at least one working head movable along a feedback path through the interior of the duct. The instruments include retainable brushes mounted on the working head which can be pressed against the interior walls of the duct to be cleaned. An injector having a suction side is connected to a suction nozzle mounted on the working head for sucking in dirt and a dust collecting bag is provided downstream.
Walton, U.S. Pat. No. 5,072,487, discloses a duct cleaning apparatus having a pneumatically powered carriage sized to fit within a duct. Nozzle means is provided for directing cleaning and disinfecting fluids under pressure at the walls of the duct to clean and disinfect the duct.
Case, U.S. Pat. No. 3,484,890, discloses a pressure-vacuum cleaning and treating device to move air under positive pressure through a duct means and directed at a surface to be cleaned. The dirt is moved out of the system by negative pressure to a filter chamber and then the air is sent back to the blower for recirculation.
None of these previous efforts are thought to teach or suggest all of the elements of the present invention, nor do any disclose all of the benefits of the present invention.
It is a primary object of the present invention to provide a portable H.V.A.C. duct cleaning system.
It is an additional object of the present invention to provide a portable H.V.A.C. duct cleaning system which is combustion driven.
It is a further object of the present invention to provide a portable H.V.A.C. duct cleaning system which is combustion driven and fueled by liquefied natural gas (propane).
It is another object to the present invention to provide a portable, yet powerful, combustion-driven H.V.A.C. duct cleaning system.
It is even another object of the present invention to provide a portable, combustion-driven H.V.A.C. duct cleaning system wherein the blower and motor are operated from the exterior of a building.
It is even an additional object of the present invention to provide a portable, combustion-driven H.V.A.C. duct cleaning system wherein ducting is run from the H.V.A.C. system within a building to the exterior of a building where the ducting is interconnected with a combustion-driven blower.
It is an additional object of the present invention to provide a portable, combustion-driven H.V.A.C. duct cleaning system having a primary filter means for filtering air between the ducting and the blower.
It is still even an additional object of the present invention to provide a portable, combustion-driven H.V.A.C. duct cleaning system having a secondary filter after the blower to further filter the air.
It is still even an additional object of the present invention to provide a portable, combustion: driven H.V.A.C. duct cleaning system having a sleeve filter for the secondary filter.
It is still even an additional object of the present invention to provide a portable, combustion-driven H.V.A.C. duct cleaning system having a HEPA filter for the secondary filter.
It is an additional object of the present invention to provide a portable, combustion-driven H.V.A.C. duct cleaning system having a blower where the blower is a tube axial blower.
It is an additional object of the present invention to provide a portable, combustion-driven H.V.A.C. duct cleaning system having a blower where the blower is a vane axial blower.
It is even an additional object of the present invention to provide a portable, combustion-driven H.V.A.C. duct cleaning system having a blower comprising two impellers in series for increasing the water column lift of the blower.
It is still even an additional object of the present invention to provide a portable, combustion-driven H.V.A.C. duct cleaning system having a blower with twin impellers, each impeller being driven by a separate combustion engine.
It is still even a further object of the present invention to provide a portable, combustion-driven H.V.A.C. duct cleaning system having a blower comprising two counter rotational impellers.
A combustion driven, portable, HVAC duct cleaning system is provided wherein the components of the system are quickly and easily attachable and detachable and are mounted on cart means to allow for mobility of the system. The system includes ducting for attaching the system to ductwork to be cleaned, a primary filter for filtering large debris, a combustion driven blower for creating an airflow, and a secondary filter for final filtering of the air prior to release into the atmosphere. The primary filter includes a breach door for opening the filter to remove filtered material therefrom. The breach door may include a transparent panel for permitting one to view the interior thereof. Preferably, the primary filter includes a wire mesh cone, the point of which extends into the air flow to provide for the filtering of large objects. The blower is preferably a tube axial blower driven by means of a belt interconnected with a combustion engine for driving the impeller within the blower to create an airflow. Thereafter, the airflow can be exhausted into a filter such as an inflatable sleeve filter or a HEPA filter such as a HEPA trailer. In an alternate embodiment, the combustion driven blower may include twin impellers driven by separate combustion engines to increase the resistance to static pressure as would be measured by water column fit. The twin impellers are preferably counter rotational to straighten airflow through the blower and to boost resistance static pressure as would also be measured by water column lift.